“…In [1], in the case where, in the //TVJV-extension G -(t, K\t~lAt = B, <p), [2] Residual finiteness of HNN-extemions 409 the base group AT is a finitely generated abelian group, a simple necessary and sufficient condition for the group G to be residually finite was given. In the present paper we generalize the results of [1] to the case where the base group is a finitely generated nilpotent group.…”